Association between a High Level of Growth Hormone–Releasing Hormone (GHRH) and GHRH Genetic Polymorphism (rs566092278) with Acromegaly Cases

Abstract Background: Acromegaly (ACM) is a rare endocrine chronic disorder. It occurs because of a benign tumor in the pituitary gland, which secretes an excess of growth hormone (GH). Objectives: The objective of this study is to determine the association between growth hormone-releasing hormone (GHRH) concentration and the GHRH (rs566092278) genetic polymorphism with the severity of ACM cases. Materials and Methods: This study, which was carried out from December 2022 to April 2023, involved 80 samples from ACM patients collected from the Diabetic National Center at Al-Mustansiriyah University, Baghdad, Iraq, along with 80 samples from healthy individuals. The measurement of GH and insulin-like growth factor-1 (IGF-1) was performed using the sandwich chemiluminescence immunoassay technique. The measurement of GHRH was performed using the enzyme-linked immunosorbent assay. Results: The concentrations of GHRH, GH, and IGF-1 were elevated with significant differences observed in ACM patients compared with controls. Sequencing results for the amplification of the GHRH gene show the rs566092278 mutation, whereby CC homozygous was observed in 80 (100%) of controls and 52 (65%) of ACM patients. The presence of CT heterozygous in ACM patients was 28 (35%). There are significant differences ( P < 0.05) between the control and ACM patients (0% vs. 35%, P = 0.008*). There is an association between GHRH concentration and the rs566092278 single nucleotide polymorphism (SNP) in the GHRH gene, whereas significant differences ( P < 0.05) in GHRH concentration between CC and CT genotypes (96.11 ± 21.8 vs. 196.2 ± 24, P = 0.008*). Conclusion: The elevation of GHRH concentration and the presence of the rs566092278 SNP in the GHRH gene were associated with pituitary adenoma that causes ACM in Iraqi patients.